"Animal health technologists (AHTs) are referred to as the 'right hand' of a
vet," says Cathy Hall-Patch, an AHT and instructor at a college's
animal health technology program. "Technologists take X-rays, [do] blood work,
collect samples, set up IVs and catheters, prep animals for surgery, induce
anesthesia and often assist the vet in surgery.

Animal health technologists need mathematical skills to do their
jobs and help their patients, notes Hall-Patch. "We use it for drug
calculations, determining dilutions, [calculating] fluid flow rates for IVs, calculating
the nutritional needs of an animal and in research [statistics
are required to figure out probabilities and rate distributions]."

It's very important to do these calculations properly -- an animal
could die if you make a mistake. This is especially true when an animal
health technologist is preparing anesthesia for an animal about to go into
surgery.

With
the class, discuss all the ways an animal health technologist would use
math. Why is using math important for them? Brainstorm answers to the
following questions:

Would it be important for an animal health technologist to know an animal's weight?
Why?

Do they ever need to convert a number from imperial measure to metric?
Why?

Is there any reason for a large dog to be treated differently medically than a small dog?
Give some examples.

In an emergency, animal health technologists must be able to do some fast calculations in their heads. Try a few on your own.

Back
to the veterinary clinic. A woman has brought her border collie in for
surgery. The vet has asked you to prep the dog and induce anesthesia.
According to the owner, the dog named Hobbes weighs about 45 pounds.
The anesthetic your clinic uses is called Pentothal. It comes in a
powder form. You've already mixed it to create a 2 percent solution.
(Some clinics use a different dilution; it can range from 2 percent to
5 percent.)

20 mg

ml

To effectively anesthetize an animal, you need to give it 10 to 12 milligrams of Pentothal per
kilogram of its weight.

Your clinic generally goes with a ratio of

12 mg

kg

You've
weighed the dog yourself to ensure his weight is 45 pounds. How many
milliliters of solution do you need to give Hobbes? (Hint 1 pound =
0.45 kg)

Additional Calculations:

1. If the solution is mixed at 5 percent, how much of it is required?

2.
Create a graph that shows the amounts of Pentothal needed for dogs
ranging from 1 kg to 80 kg. Plot both the 2 percent and 5 percent
solutions on the same axis.

3. Using the graph, calculate how much each of these dogs will need of either solution:

8 kg

27 kg

46 kg

4.
A dog food manufacturer recommends that you feed your dog 60 g of their
food for every 5 kg the dog weighs. Create a graph comparing the dog's
mass to the amount of food recommended.

The Pentothal is made up into a 2 percent solution (20 mg/ml), so how many milliliters of solution is needed?

243 mg

(20 mg/ml)

= amount of solution required

Approximately 12.15 ml are required to adequately anesthetize Hobbes for his surgery.

"It's very important to think it through logically and do it step by step,"
says Hall-Patch. It's hardest to figure out the amount of solution that is
required. "My students often stumble at that step."